Floor and wall covering



Jan. 4, 1949. w. STUBBLEBINE FLOOR AND WALL CVOVERING 2 Shawna-sheenl 1Filed July 31, 1943 FIG.

Jan. 4, 1949.

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PERCENT INITIAL gnam/who@ Patented Jan. 4, 1949 2,457,848 l C E FLOORANI) WALL COVERING Warren Stubblebine, Manheim Township, LancasterCounty, Pa., assignor to Armstrong Cork Company, Lancaster, Pa., acorporation of Pennsylvania Application July 31, 1943, Serial N0.496,967

9 Claims.

This invention relates to licor and wall coverings and more particularlyto a floor or wall covering suitable for use in structures where freealkali is present and capable of withstanding adverse conditions whichwould normally completely deteriorate linoleum type coverings.

In modern homes, it is common practice to utilize a portion of thebasement for recreation rooms, bars, and the like, and, in order thatthe floors and walls may have an attractive appearance, they are eitherpainted or covered with a flexible hard surface covering. Where theiioor and wall surfaces are below grade, there is the problem of.providing a covering which is not deleteriously attacked by the freealkali which appears at the surface of the concrete .iloor and wallareas, aggravated by water which is generally always present in belowgrade installations. All oil paints are unsatisfactory for this purposeand special alkali resistant paints have been devel- 90 oped for thisuse. Linoleum floor and wall coverings, while ideally suited from thestandpoint of decoration, are so badly affected by alkali that theycannot be used. Asphalt tile is suitable for this purpose because theasphalt binder is not saponiled by the free alkali. Tiles made with anasphalt binder, however, are not attractive because of their dark colorsand, as a consequence, especially developed binders have been producedwhich are resistant to such attack. These tiles are generally installedin pieces, say 9" x 9" squares, and when unusual effects are desired,the tile mustbe heated and cut and this can be accomplished only withgreat skill and at considerable expense. Tiles of this sort are no1;generally used on wall surfaces because of their cost and alsobecausethey are designed primarily for withstanding wear and areconsequently relatively thick. Even with these special binders, thecolors available are relatively limited, being generally in the darkershades.

There is also a demand for a flexible hard surface floor covering whichcan be applied directly to concrete, such as suspended concrete floors,which has just set, without waiting'the usual period of three months foriinal curing of the concrete. In this condition, there is considerablefree alkali present until nal curing has been accomplished and theilexible floor coverings now available; such as linoleum, cannot' beinstalled immediately after the cement has hardened, but

installation must be delayed until months after Vthe building has beencompleted.

It is an object of my invention to provide a exible hard surface flooror wall covering which is capable of withstanding attack by i'ree alkaliwithout materially changing its physical characteristics, such asinitial penetration, residual indentation, flexibility, resilience,surface hardness, or wear resistance, and which-may be safelyincorporated into a building structure in which 2 there is a base suchas a concrete iloor or wall surface, where free alkali is present ormade available through a leaching effect, particularly induced by waterpresent in below grade installations.

Another object of my invention is to provide a flexible hard surfacefloor or wallcovering which may be incorporated into such structures andwhich may be produced in substantially continuous lengths withoutnecessity for curing or stoving as is common practice in the manufactureof linoleum.

In attaining these objects, I provide a. covering which is suitable forgeneral iioor and wall covering uses, having unusual characteristics;particularly good exibility, low initial penetration and residualindentation, and high resistance to alkali, such as present in strongsoaps and cleaning powders.

Floor or wall coverings, in order to be acceptable, should meet theminimum specications set out in Federal speciilcation LLL-L-367, datedSeptember 15, 1942, with respect to indentation under item E-4 andpliability under item E-6. In the-indentation test, a disc of thecovering material is supported upon a steel plate and a pressure of3,200 pounds per square inch is applied to the upper surface of thesample for a period of thirty seconds by means of a fiat-endedcylindrical steel bar 0.178 inch in diameter. The load is lowered gentlyuntil the bar is in full contact with the sample and the sample in fullcontact with the plate. 'After thirty seconds, the load is quickly andcompletely removed. Sixty minutes after removal of the load the residualindentation is measured to the nearest thousandth of an inch andcalculated as percentage of the original thickness. This percentage gureis known as the per cent of residual indentation and, in accordance withthe Federal specification referred to, must not exceed 10%. Thepenetration of the bar into the sample at the end of the thirty secondsapplication of pressure is also measured and this is known as theinitial penetration. While the Federal specifications have no specicprovision for initial penetration, the oor covering industry generallyconsiders a product unsatisfactory if the initial penetration is greaterthan 50%. vvWhere the terms initial penetration" and"residua1`indentation are used herein, I mean the initial penetrationand residual indentation determined in accordance with the foregoingprocedure.

The pliability test is determined by cutting a strip 2 inches wide by 8inches long longitudinally of the covering and a similar strip of thesame size transversely of the covering. These strips are bent with thebacking, if one is employed, on the inside. The bend is made atapproximately the` center of 'the sample over a mandrel 2V: inches indiameter to an arc of 180 and at dium hydroxide, and linseed oil tests.

approximatelyV a uniform speed in approximately 5 seconds. Any breakingor cracking is noted and, if so little as surface cracks appear, theproduct is unacceptable.

A test which is believed to be more indicative of the exibility of oorcovering products and one which has been employed by the linoleumindustry is the so-called Tinius-Olsen Stillness test. This test is alsocommonly used in the testing of wire, tinplate, felt, and othermaterials. One-eighth inch linoleum, when tested by this method on aTinius-Olsen machine, shows a break angle of about 50 and a per cent ofweight of about 60% to 65%. These results do not materially change overlong periods of time, indicating that linoleum is a relatively stableproduct with respect to exibility. The trade expects any product whichwill be used for floor and wall covering purposes to possess at least anequivalent degree of iiexibility.

Other tests commonly employed to determine the physical characteristicsof hard surface floor coverings are water immersion, soap solution, so-

of these tests,the sample is immersed in the treating solution for 18hours at a temperature of '70 F. The samples are removed from thesolution, wiped dry, and thengiven the standard initial penetration andresidual indentation test above described in connection with Federalspecification IIL-1F36?. In the soap test, a neutral 1% soap In eachsolution is used and this test gives a general indication of the effecton indentation resulting from frequent washing with mild soaps. The

sodium hydroxide test in which the sample is immersed in a 2% sodiumhydroxide solution is of particular importance, for by this test it ispossible to determine whether a floor covering is satisfactory for usein those structures where it will be brought into contact with freealkali. It has been determined that those materials which havel aninitial pentration greater than '15% in this test are wholly unsuitedfor this purpose. As a matter of fact, those materials which show aninitial penetration greater than are not desirable. Products likelinoleum are completely dissolved in a 2% sodium hydroxide solution inabout 6 hours, indicating clearly that such products are notsatisfactory for this use. This test also shows the durability of theproduct under unsatisfactory cleaning conditions where harsh soaps andcleaners are used.

'I'he covering of this invention is formed with a binder composed of aspecial phenol-modified coumarone-indene resin modified with a celluloseether such as ethylcellulose. The phenol-modiiied coumarone-indene resinemployed may be produced by the simultaneous polymerization and reactionof the polymerizables contained in hydrocarbon liquids such as crudesolvent naphtha and a phenol or phenolic substance. More specifically,the resin can be prepared by mixing and heating crude solvent naphthaand cresol with activated clay at a temperature of about C. to C. untila resin is formed. The reacted mixture is filtered to remove theactivated clay and the mixture is then subjected to an initialdistillation to remove the nonpolymerizable portion of the naphtha andany unreacted cresol. The residue is separated by steam distillationinto a relatively hard resin fraction and a heavy viscous resin fractionhaving a melting point between 5 C. and 15 C. as determined by the cubein mercury test. It is this heavy viscous fraction 4 suitable since itdoes not have the desirable effect of toughening and improving theworking characteristics of the composition. The phenol-modiedcoumarone-indene resin so prepared possesses some unusualcharacteristics which make it ideally suited for my purpose. While I donot wish to be limited to any theory. it is my belief that there is aparticular -OH grouping in the resin which results in the unusualproperties which are obtained when this material is combined with acellulose ether in the preparation of my binder. One distinguishingchemical characteristic of this resin is that it is soluble in alcohol,whereas other resins of a similar nature having higher melting pointsare not soluble in such solvent. By the term alcohol solublephenolmodiied coumarone-indene resin having a melting point between 5 C.and 15 C., as recited hereinafter in the specification and claims, Imean a product such as that obtained in accordance with the procedureset forth above, or one that is substantially identical with it eventhough prepared by a different procedure.

While I prefer to use ethylcellulose as a modiiier in combination withthe phenol-modified coumarone-indene resin, other cellulose ethers suchas benzylcellulose or any other cellulose ether which is compatible withthe phenol-modifled coumarone-indene resin may be employed. Thephenol-modified coumarone-indene resin constitutes the major portion ofthe binder and preferably is in the order of about 55% to 65% of thetotal binder. A specific example of the binder is as follows. Parts byweight Alcohol soluble phenol-modified coumaroneindene resin having amelting point between 5 C. and 15 C 125 Ethylcellulose '25 This binderhas a melting point between 103 C. and 112 C. and is prepared bycharging the resin into a mixing kettle heated to about 300 F. Theethylcellulose is then charged into the kettle containing the resin andagitation is accomplished to effect an intimate distribution. Uponheating, the materials are dissolved and are combined to form a highlyviscous binder. This viscous mass is then charged into a mixer, such asa Werner- Pfleiderer mixer, and the llers and-pigments are there added.The mixer is heated to about 300 F.

A typical oor or wall covering composition is asfollows. by weightBinder prepared as above Serpentine l 225 Ground limestone 210 Cork dust50. Coloring pigments 45 longer mixing time than those of a coarsernature. After a homogeneous mixture has been obtained, the batch isdischarged from the german mixer into a two-roll scratcher, which iseffective for breaking the mass into fine particles suitable forcalendering. The .granules are then calenwhich I employ. The hard resinportion is un- 15 dered. At this point in the operation, a backing.

such as burlap or cotton fabric or asphalt saturated felt, or the likemay be used. I wish it to be understood that the covering of thisinvention possesses suilicieiit strength that a backing is not required.The calender is generally of the tworoll type having a heated face rolland a cooled back roll. The face roll may be heated from 250 F. to 300F. so as to produce a finished sheet having a high gloss exposedsurface, and the back roll is preferably maintained at 100 F. or less.

The material as it comes from the calender roll is completely finishedand ready for use upon cooling. This should be contrasted to the usualtype linoleum floor coverings where, after calendering, the materialmust be hung in heated curing stoves for periods ranging from 6 days to3 weeks. Where the quantity produced by a man-- ufacturer is relativelylarge, the stove capacity is a major factor in limiting production.yWith the covering of my invention, all of this equipment is` dispensedwith and the product as calendered is run through a cooling zone andthen and packaged for shipment.

From the foregoing specific example, it will be observed that the bindercomprises about 25% of the total weight of the mass. Preferably, thebinder is in the order of to 40% and the liller is from about 60% to80%. The particular type of fillers chosen is not important.Satisfactory results have been obtained where both organic and inorganicfillers have been used. My composition is of a resiient nature even withmineral fillers and, accordingly, it is not necessary to use a highpercentage of resilient organic type lling materials, such as cork orwood flour commonly used in the manufacture of linoleum to impart thedesired resilience. Organic fillers are general'y much more expensivethan inorganic llers and many are subject to attack by alkali. With mycomposition, the ratio of llers to binder may be extremely high and goodilexibility and resilience will obtain, thus decreasrolled up ing thecost of the product and making the use of large quantities of organicfillers which may be bady attacked unnecessary. This is due to theunusually good binding value of the binder of my composition. Inmyresearch work on this problem, I tried various compositions in whichcellulose ether was modified and others in which cellulose ether was themodifier and, in practically all instances. it was impossible toincorporate as much as 50% of filler; most compositions satisfactorilyheld only to 40% of filler.

I have found that where both organic and inorganic flllers are employeda ratio of organic to inorganic llers of from 1 to 6 and from 1 to 9 isdesirable, and satisfactory results have been obtained when one part byWeight of organic filler, such as cork, is used with 8 parts ofinorganic liiler such as serpentine and ground limestone,

as in the specific example given above.

An example of a binder utilizing another cellulose ether is as follows:

Parts by weight yAlcohol soluble phenol-modified coumaroneindene resin100 Benzylcellulose 52 Reference is made to the attached drawings, inwhich Figure 1 is a diagrammatic view showing my covering applied to aconcrete base such as a floor;

Figure 2 is a similar view showing a modified covering applied to aplastered wall surface;

Figure 3 is a chart which illustrates the physical properties of mymaterial;

Figure 4 is a table comparing the Tinius-Olsen Stiifness test on mycomposition with that of linoleum; and

Figure 5 ls a graph illustrating the effect on initial penetrationresulting from aging.

Referring to Figure 1, there is shown 'a base 2 which may be a freshlaid concrete floor or floor below grade to which ordinary linoleum typehard surface iloor or wall coverings could not be satisfactorilyapplied. Adhesively secured to the base 2 by a layer of adhesive 3 is acovering 4 composed of a backing layer 5 and a wearing layer 6. Thewearing layer 6 is of the composition referred to above, formed offiller and pigment particles and a binder composed of alcohol solublephenol-modified coumarone-indene having a melting point of 5 C. to 15 C.and a cellulose ether.

Figure 2 shows a modification of my invention in which the base 2 is aplastered. wall surface which has a covering 4 adhesively secured there-'to by a layer 3', the covering having no backing or foundation layersuch as the layer 5 of Figure 1.

Reference is now made to the chart constituting Figure 3. From this itwill be observed that the product of this invention is not substantiallyaffected by water, a 1% soap solution, or linseed oil. The reallysignificant factor, however, is the result obtained on the 2% sodiumhydroxide test. Referring specifically to this portion of Figure 3, itwill be noted that the control specimen shows an initial penetration ofabout 29%. The sample treated with the 2 sodium hydroxide showssubstantially identical initial penetration. The residual indentation ofthe control specimen was 4.1% and the corresponding figure after thesodium hydroxide test was 9.1%. This proves that the material is onlyslightly softened under this test and does not deteriorate likelinoleum. It falls Well below the 5.0% initial penetration permitted ofa covering suitable for use inthose installations below grade and foruse on relatively fresh concrete. As heretofore pointed out, linoleumcompletely deteriorates in 6 hours under such conditions.

In order to further compare resistance of my product with that ofcommercially avaiable linoleum, I have conducted the so-called wet weartest, which consists essentially of abrading a sample of the materialwith sand and steel balls for twenty minutes while subjected to a 5%sodium hydroxide solution. My product showed a loss of 1.42% in thistest, whereas a commercial linoleum showed 5.46% loss. In the same testextended to 40 minutes, my product showed a loss of 2.46% and thelinoleum a loss of 11.9%.

The chart of Figure 4 compares the flexibility of the product of myinvention with that of linoleum in accordance with the Tinius-OlsenStiffness test using a weight of 8/in. pounds on the linoleum sample and2/in. pounds on the more flexible material of this invention. It will benoted that the break angle on the linoleum was 50 and this is generallythe angle at which linoleum of 1A," gauge br'eaks. At that angle thelinoleum was supporting about 61.5% of the weight. With my material nobreak occurred even at the top of the scale; namely, 90. and with thesample supporting 85% of the weight. As a matter of fact, no surfacecracks were observed at 90. This establishes that the composition oil myinvention is more flexible. gauge for gauge, than linoleum.

Figure compares the initial penetration of linoleum and my compositionupon aging. These tests were made with conditions of 70 F. and 65%relative humidity prevailing throughout. The chart indicates that theinitial penetration of linoleum increases upon aging, indicating thatthe product generally softens. This has been determined by other workersin the field to be due to water absorption. The product oi' my inventionshows an initial penetration of around 25%, increasing to about 36% overa two-day period and then decreasing to about 28%, maintaining aboutthis initial penetration throughout the duration of the examination;namely, 180 days.

While I have described my invention particularly with reference .toflexible iloor and wall coverings and have compared it with linoleum, myinvention is not limited to products of this character but contemplatetiles and other iioor or wall coverings which may be relatively hard andrigid. My invention may be otherwise embodiedand practiced within thescope of the following claims.

I claim:

1. A hard surface :door or wall covering or the like comprising fromabout 20% to about 40% by weight of a binder composed essentially offrom about 55% to about 65% of an alcohol soluble phenol-modiiledcoumarone-indene resin having a melting point between 5 C. and 15 C.,and from about 35% to about 45% of an alkali-insoluble cellulose etherselected from the group consisting of ethylcellulose andbenzylcellulose; 4and from about 60% to about 80% by weight oi illlingmaterial.

2. A hard .surface iloor or wall covering or the like comprising awearing layer having an initial penetration as herein dei'lned of notmore than 50% after immersion for 18 hours in a. 2% sodium hydroxidesolution and a residual indentation as herein dened of not more thancomprising from about 60% to about 80% by weight oi illng material andfrom about to about 40% by weight of a binder composed essentially offrom about 55% to about 65% of an alcohol soluble phenol-modiiledcoumarone-indene resin having a melting point between about 5 C. andabout 15 C. combined with from about 35% to about 45% of analkali-insoluble ethylcellulose.

3. A hard surface door or wall covering or the like comprising fromabout 20% to about 40% by weight of a binder composed essentially offrom about 55% to about 65% of an alcohol soluble phenol-modifiedcoumarone-indene resin having a melting point between 5 C. and 15 C..and from about 35% to about 45% of an alkaliinsoluble ethylcellulose;and from about 60% to about 80% by weight of illling material.

4. A hard surface iloor or wall covering or the like comprising fromabout 20% to about 40% by weight of a binder composed essentially offrom about 55% t0 about 65% of an alcohol soluble phenol-modifiedcoumarone-indene resin having a melting point between 5 C. and 15 C.,and from about 35% to about 45% of benzylcellulose; and from about 60%-to about 80% by weight of illing material.

5. A'hard surface floor or wall covering or the like comprising about`%by weight of a, binder composed essentially of from about 55% to about65% of an alcohol soluble phenol-modified coumarone-indene resin havinga melting point between 5 C, and 15 C., and from about 35% to about 45%oi an alkali-insoluble cellulose ether selected from the groupconsisting of ethylcellulose and benzylcellulose; and abou-t by weightoi lling material.

6. A door or wall covering or the like compris- .ing about 175 parts byweigh-t of a binder essentially composed of about 125 parts by weight ofan alcohol soluble phenol-modified coumaroneindene resin having amelting point between 5 C. and 15 C., and about 75 parts by weight of analkali-insoluble ethylcellulose; about 485 parts by weight of illlingmaterial; and coloring pigments.

7. A hard surface oor or. wall covering or the like comprisin-g fromabout 20% -to about 40% by weight of a binder composed essentially of yparts by weight of an alcohol soluble phenolmodified coumarone-indeneresin having a melting point between 5 C. and 15 C., and about 52 partsby weight of benzylcellulose; and from about 60% to about 80% by weightof filling material.

8. A hard surface floor or wall -covering or the like comprising awearing layer having an initial penetration as herein defined of notmore than 50% after immersion for 18 hours in a 2% sodium hydroxidesolution and a residual indentation as herein dened oi. not more than10% comprising from 'about 60% to about 80% by weight of fillingmaterial and from about 20% to about 40% by weight of a binder .composedessentially of from about 55% to about 65% of an alcohol solublephenol-modified coumarone-indene res'ln having a melting point betweenabout 5 C. and about 15 C. combined with from about 35% to about 45% ofan alkali-insoluble ,cellulose ether selected from the group consistingof ethylcellulose and benzylcellulose.

9. A hard surface floor or wall covering or .the like comprising awearing layer having an initial penetration as herein defined of notmore than 50% after immersion for 18 hours in a 2% sodium hydroxidesolution and a residual indentation as herein deined of not more than10% comprising from about 60% to about 80% by wei-ght of illlingmaterial and from about 20% `to about 40% by weight of a binder composedessentially of from about-55% to about 65% of an alcohol solublephenol-modified coumarone-indene resin having a melting point betweenabout 5 C, and about 15 C. combined with from about 35% t0 about 45% ofbem'ylccllulwe.

WARREN STUBBLEBINE.

REFERENCES CITED The following references are of record in the ille ofthis patentz UNITED STATES PATENTS Number Name Date 1,625,416Li-lienfeld Apr. 19, 1927 2,098,362 Rivkin Nov. 9, 1937 2,145,648 Fawkeset al Jan. 31, 1939 OTHER REFERENCES Lorand, Ind. 8: Eng. Chem., May1938, pp.-

Certicate of Correction Patent No. 2,457,848. January 4,1949. WARRENSTUBBLEBINE It is hereby certified that error appears in the printedspecification of the above numbered patent requiring correction asfollows:

Column 5, line 56, for the word and after the numeral 6 read to;

and that the said Letters Patent should be read with this correctiontherein that the same may conform to the record of the case in thePatent Oice.

Signed and sealed this l26th day of April, A. D. 1949.

THOMAS F. MURPHY,

Assistant Oommz'moner 0f Patents.

